Neoprene rubber is a synthetic rubber produced by the polymerization of neoprene. Neoprene rubber has high strength, good plasticity, medium elasticity, oxygen and ozone resistance, and oil resistance. It has strong adhesion to many substances, good flame resistance and wear resistance, and low air permeability.
The solubility parameter of neoprene rubber accounts for δ=9.2～9.41. Soluble in toluene, xylene, ethylene dichloride, trivanadium ethylene, slightly soluble in acetone, methyl ethyl ketone, ethyl acetate, cyclohexane, insoluble in n-hexane, solvent gasoline, but soluble in good solvents in appropriate proportions It is a mixed solvent composed of poor solvent and non-solvent or poor solvent and non-solvent, which swells in vegetable oil and mineral oil without dissolving.
Neoprene rubber has good physical and mechanical properties, oil resistance, heat resistance, flame resistance, sunlight resistance, ozone resistance, acid and alkali resistance, and chemical resistance. The disadvantage is poor cold resistance and storage stability. Has high tensile strength, elongation and reversible crystallinity, good adhesion. Aging resistance, heat resistance. Excellent oil and chemical resistance. Weather resistance and ozone aging resistance are second only to ethylene propylene rubber and butyl rubber. The heat resistance is comparable to that of NBR rubber, the decomposition temperature is 230-260°C, the short-term resistance is 120-150°C, and the long-term use at 80-100°C has certain flame retardancy. Oil resistance is second only to NBR rubber. Good resistance to inorganic acid and alkali corrosion. The cold resistance is slightly poor, and the electrical insulation is poor. The storage stability of raw rubber is poor, and the phenomenon of "self-sulfur" will occur, the Mooney viscosity will increase, and the raw rubber will become hard.
Neoprene rubber is an indispensable and important special synthetic rubber material in the rubber product processing industry. Neoprene rubber is widely used in general industrial products, anti-weathering products, viscose soles, coatings and rocket fuel, auto parts, wire and cable jackets and adhesives, etc. Ordinary neoprene tends to crystallize at room temperature. Therefore, anti-crystallization improved varieties were developed which were copolymerized with specific monomers to inhibit molecular alignment.
NBR rubber is a copolymer obtained by the polymerization of butadiene and acrylonitrile monomers. The full name is Nitirle-Butadene Rubber. It has excellent oil resistance, benzene resistance, heat resistance and physical and mechanical properties. NBR rubber is one of the general raw materials for oil-resistant rubber products. NBR rubber is widely used in the manufacture of oil-resistant gaskets, gaskets, hoses, airplane mailboxes, flexible packaging, printing and dyeing rubber rollers, cable materials and adhesives Wait.
NBR rubber has the following properties:
Oil resistance is the biggest feature of NBR rubber. Because it contains polar cyano groups, it has high stability to non-polar or weakly polar oils and organic solvents, and its oil resistance is second only to polysulfide rubber and fluor rubber. The higher the propylene content, the better the oil resistance.
High and low temperature resistance:
The heat resistance is better than that of natural rubber, styrene-butadiene rubber, and neoprene rubber, and can be used for a long time at 120 ℃ in the air. The cold resistance and low temperature resistance are poor, the higher the acrylonitrile content, the worse the cold resistance. With the increase of acrylonitrile content, the tensile strength, heat resistance, oil resistance, air tightness and hardness increase, but elasticity and cold resistance decrease. The glass transition temperature of nitrile rubber with 26% acrylonitrile content is -52°C, and the embrittlement temperature is -47°C; while the glass transition temperature of nitrile rubber with 40% acrylonitrile content is -22°C.
Pretty good, only second to butyl rubber.
Ozone resistance, electrical insulation properties, water resistance
NBR rubber has poor ozone resistance and electrical insulation properties, and good water resistance.
The solubility parameter of NBR rubber is 8.9~9.9, and it is soluble in ethyl acetate, butyl acetate, chlorobenzene, methyl ethyl ketone, etc.
NBR rubber has poor dielectric properties and belongs to semiconductor rubber.
NBR rubber is non-crystalline rubber with low raw rubber strength. It needs to be mixed with reinforcing agents. Increasing the amount of combined acrylonitrile helps to increase the strength and wear resistance, but the elasticity decreases.
Due to its strong polarity, it has poor compatibility with polymers with weak polarity, but it is not compatible with polymers with strong polarity such as neoprene, modified phenolic resin, and polyvinyl chloride, especially with chlorine-containing polymers. The polymers have good compatibility and are often used in combination. In addition, in order to improve processing performance, it is often used with non-polar rubbers such as natural rubber, styrene-butadiene rubber, and butadiene rubber.
Main use of NBR rubber
Nitrile rubber is mainly used to make oil-resistant products, such as oil-resistant pipes, tapes, rubber diaphragms and large oil bags, etc. It is often used to make various oil-resistant molded products, such as O-rings, oil seals, leather cups, diaphragms, valves, bellows, etc., are also used to make rubber sheets and wear-resistant parts.
Properties and uses of NBR rubber rolls
①Excellent wear resistance;
②The oil resistance is 30%-50% higher than that of natural rubber;
③ Good heat resistance, but not ozone resistant;
④ Excellent resistance to non-polar and weakly polar oils and solvents, but poor resistance to aromatic hydrocarbons and chlorinated hydrocarbon oils. Commonly used in printing, printing and dyeing, papermaking, packaging, chemical fiber, plastic processing and other equipment and other occasions contacting oil and aliphatic hydrocarbon solvents.
Properties and uses of neoprene rubber rolls
Neoprene rubber rolls are a synthetic rubber with very similar physical properties to natural rubber. Neoprene rubber rolls have better weatherability than natural rubber, with moderate resistance to oil, heat and ozone fluids.
Typical applications for neoprene rubber rolls include conveyor belts, coated fabrics, cable jackets, seals and leggings.
From the above analysis, we know that neoprene rubber roll is more suitable for industrial belts than the NBR rubber roll.